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 A081357 Sublime numbers, numbers for which the number of divisors and the sum of the divisors are both perfect. 4
 12, 6086555670238378989670371734243169622657830773351885970528324860512791691264 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(2) was calculated by K. S. Brown. REFERENCES J.-M. De Koninck, Those Fascinating Numbers, Amer. Math. Soc., 2009. M. J. Halm, More Sequences, Mpossibilities 83, April 2003 C. A. Pickover, Wonders of Numbers, p. 215 LINKS K. S. Brown, Odd Sublime Numbers (posting to sci.math newsgroup) K. S. Brown, Sublime Numbers J. Griffiths, Lopsided numbers, Mathematical Spectrum, 43 (No. 2, 2010/2011), 53-54. Dean Hickerson, Re: Twelve is special (posting to sci.math newsgroup) C. A. Pickover, "Wonders of Numbers, Adventures in Mathematics, Mind and Meaning," Zentralblatt review GĂ©rard Villemin, Nombre sublime (French) EXAMPLE a(1) = 12 because 12 + 6 + 4 + 3 + 2 + 1 = 28 is perfect and number of divisors, 6, is also perfect. CROSSREFS Sequence in context: A144546 A165970 A285180 * A127708 A094896 A277118 Adjacent sequences:  A081354 A081355 A081356 * A081358 A081359 A081360 KEYWORD hard,nonn,bref,more AUTHOR Michael Joseph Halm, Apr 20 2003 STATUS approved

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Last modified April 8 09:44 EDT 2020. Contains 333313 sequences. (Running on oeis4.)